view core/client.cpp @ 37:b3661e68918c bbb_network

Closed bbb_network branch

///* UDP client in the internet domain */

#include <ctype.h>
#include <sys/time.h>
#include <fcntl.h>
#include "../include/client.h"
#include <unistd.h>
#include <rtdk.h>

#define BUFF_LEN 1024
#define MAX_VAR_STRING 20

struct sockaddr_in outServer, inServer;
int outSock, inSock, n, length;
socklen_t fromlen;
struct sockaddr_in from;
char inBuffer[1024];
char variableString[MAX_VAR_STRING];

int setupSockets(int receivePort, int transmitPort, char const*serverName){
	//setup transmitter
	printf("receivePort: %d; transmitPort: %d; serverName: %s\n",receivePort, transmitPort, serverName);
	outSock= socket(AF_INET, SOCK_DGRAM, 0);
	outServer.sin_port = htons(transmitPort);
	if (outSock < 0){
		error("Opening out socket");
		return -1;
	}
	outServer.sin_family = AF_INET;
	inet_pton(AF_INET,serverName,&outServer.sin_addr);

	//setup receiver
	inSock=socket(AF_INET, SOCK_DGRAM, 0);
	if (inSock < 0){
		return -1;
		error("Opening in socket");
	}
	length = sizeof(inServer);
	inServer.sin_family=AF_INET;
	inServer.sin_addr.s_addr=INADDR_ANY;
	inServer.sin_port=htons(receivePort);
	if (bind(inSock,(struct sockaddr *)&inServer,length)<0)
	   error("binding");
	fromlen = sizeof(struct sockaddr_in);
	return 0;
}
int sendMessage(networkData message)
{
   unsigned int length;
   char buffer[BUFF_LEN];
   length=sizeof(struct sockaddr_in);
   int k=0;
   k=sprintf(buffer+k, "%8d;",*message.counter);
   for(int j=0; j<message.numVariables; j++){
	   k+=sprintf(buffer+k, "%.3f;",*message.variables[j]);
	   if(k>BUFF_LEN - 20) //safety margin
		   continue;
   }
   sprintf(buffer+k,"\n");
  // printf(buffer);
   n=sendto(outSock,buffer,
            strlen(buffer),0,(const struct sockaddr *)&outServer,length);
   if (n < 0) error("Sendto");
   return 0;
}
/*
int receiveMessage()
{
   int n = recvfrom(inSock,inBuffer,1024,0,(struct sockaddr *)&from,&fromlen);
   if (n < 0) error("recvfrom");
   printf("Received a datagram: ");
   printf(inBuffer);
 }
*/


int receiveMessage(networkData message){
	struct timeval stTimeOut;
	fd_set stReadFDS;
	FD_ZERO(&stReadFDS);
	// Timeout of one second
	stTimeOut.tv_sec = 0;
	stTimeOut.tv_usec = 0;
	FD_SET(inSock, &stReadFDS);

	int t = select(inSock+1, &stReadFDS, NULL, NULL, &stTimeOut);
	if (t == -1) {
		rt_fprintf(stderr, "Call to select() failed");
		return -1;
	}
	else if (t != 0) {
		if (FD_ISSET(inSock, &stReadFDS)) {
//			printf("There is data pending to be read..."); // Read data with recv()
			int n = recvfrom(inSock,inBuffer,1024,0,(struct sockaddr *)&from,&fromlen);
			if (n < 0){
				rt_fprintf(stderr,"Error while receiving");
				return -1;
			}
			printf("Received a datagram: ");
			printf(inBuffer);
			//the worst parser ever
			int previousN=0;
			int currentVariable=0;
			for(int n=0; inBuffer[n]!=0 && currentVariable<message.numVariables && n-previousN<MAX_VAR_STRING && n<BUFF_LEN; n++){ //scan the string
				if(inBuffer[n]==';'||inBuffer[n]==0||inBuffer[n]=='\n'){ // if you find a separator or you are at the end of the string, parse the variable
					int j=0;
					inBuffer[n]=0;	 //set the semicolon to 0 ...
					while( (variableString[j++]=inBuffer[previousN++]) );; // ... so that this will stop when it gets there
					rt_printf("variable %d: %s\n", currentVariable, variableString);
					*(message.variables[currentVariable])=atof(variableString);
					n++; //increment to step after the semicolon
					previousN=n;
					currentVariable++;
				}
			}
		}
	}
	return 0;
}

void closeSockets(){
   close(outSock);
   close(inSock);
}
void error(const char *msg)
{
    perror(msg);
    exit(0);
}